Centrifugal amalgamator



y 1, 1956 'D E. WAHLER ETAL 2,743,866

CEN'IIRIFUGAL AMALGAMATOR Filed Dec. 10, 1954 2 Sheets-Sheet l May 1, 1956 D. E. 'WAHLER ET AL 2,743,866

CENTRIFUGAL. AMALGAMATOR Filed Dec. 10, 1954 2 Sheets-Sheet 2 'IIIIIIIIIII I IIIIIIIIIIIIIIIYII,VII1'//Il F United States Patent CENTRIFUGAL AMALGAMATOR Dale E. Wahler and Leon P. Wahler, Stockton, Calif., and Gerard V. Smith, Fayetteville, Ark; said Smith assignor to said Dale E. Wahler and said Leon P. Wahler Application December 10, 1954, Serial No. 474,554.

8 Claims. (Cl. 233-14) This invention relates to, and it is a major object to provide, a centrifugal type machine for the recovery of heavy metals or values such as gold, or the like, from fine crushed ore pulp by means of the mercury amalgamation process.

Another important object of the present invention is to provide a machine, for such purpose, which includes a high speed vertical axis cylinder having a novel lining adapted for the retention of the mercury during operation of such machine.

An additional object of the invention is to provide a novel feed system for the initial deposit of the mercury in the rotating cylinder and subsequent continuous delivery of fine crushed orein pulp form--into said cylinder adjacent the top thereof.

Still another object of the invention is to provide the machine with means to subject the ore pulp, as it passes downwardly in the rapidly rotating cylinder, to a forceful water spray which aids in the amalgamation of the values with the mercury carried by the cylinder lining; the water from such spray serving of course to constantly flush the pulp downwardly in said cylinder for discharge from the lower end of the latter.

A further object of the invention is to provide a centrifugal amalagamator as above which includes a novel receiving bowl into which the gangue from the cylinder discharges; said bowl having a discharge pipe assembly associated therewith, and arranged so that the level of water or gangue delivery from the bowl is above the bottom of the latter, whereby the lower portion of the bowl may receive values or amalgam without loss.

It is also an object of the invention to provide a centrifugal amalgamator which is designed for ease and economy of manufacture, with simplicity of operation, and maximum service with little repair of servicing being required.

Still a further object of the invention is to provide a practical and reliable centrifugal amalgamator, and one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will full appear by a perusal of the following specification and claims.

In the drawings:

Fig. 1 is a side elevation, mainly in section and partly broken away, of the centrifugal amalgamator.

Fig. 2 is a sectional plan view on line 2-2 of Fig. 1.

Fig. 3 is an enlarged fragmentary radial section of the cylinder and its lining; mercury being shown in the grooves, as when the machine is in operation.

Referring now more particularly to the drawings and to the characters of reference marked thereon, the centrifugal amalgamator comprises an upstanding heavy duty frame indicated generally at 1; such frame preferably being of tubular construction, rectangular in plan, and including corner posts 2. The corner posts 2 are conice nected together on each side of the frame by a plurality of cross bars 3.

A vertical axis amalgamating cylinder 4 is disposed within the confines of the frame 1 in a central position, and with the lower end of said cylinder some distances above the ground or floor level.

The vertical axis amalgamating cylinder 4 is supported in frame 1 for high speed rotation, in the following manner:

The cylinder 4 is fitted adjacent the top and bottom thereof with annular, horizontally disposed upper and lower carrier rings, indicated at 5 and 6 respectively.

Slightly below the rings 5 and 6, and radially out therefrom the frame supports, by braces 7, upper and lower mounting rings, indicated at 8 and 9 respectively.

Circumferentially spaced horizontal axis rollers 10 and vertical axis rollers 11 are secured to the mounting rings 8 and 9 to rotatably support and prevent lateral displacement of the carrier rings 5 and 6 as well as the amalgamating cylinder 4.

Such cylinder is adapted to be rotated at relatively high speed by means of unitary pulley 12 formed on the cylinder intermediate its ends, which pulley is driven by multi-- ple endless belts 13 from a drive pulley 14 on a vertical axis electric motor 15 secured to the frame 1 at one side thereof.

A downwardly and inwardly inclined pulp feed pipe 16 overhangs the cylinder 4 to substantially the vertical axis thereof; such pipe being fixedly supported by an assembly of a cradle 17 and clamps 18.

Fine crushed ore pulp is adapted to be fed through the pipe 16 from a valve controlled source (not shown).

At its inner end the pulp feed pipe 16 is formed with a down-turned elbow 19 which merges and communicates with a plurality of downwardly divergent circumferentially spaced distributor pipes 20 which terminate at their lower ends within the upper portion of the cylinder 4 adjacent but clear of the same thereof. At their lower ends the distributor pipes 20 each are formed with a nozzle 21 which discharges in the direction of rotation of said cylinder.

A receptacle 22 for mercury is supported from pipe 16, preferably adjacent the elbow 19, and a pipe 23 leads downwardly from this receptacle to a termination adjacent and in facing relation to the topmost one of a row of mercury receiving grooves in the cylinder 4, as will shortly be described. A hand control valve 23a is interposed in pipe 23.

The amalgamating cylinder 4 is fitted internally and for its full height with a lining 24 of rubber or similar resilient material; the inner face of the lining 24 being formed with a multiplicity of full-circle, vertically spaced, grooves 25 of substantial depth.

A water supply pipe 26, having a valve 27 therein, leads over the frame 1 below the pulp feed pipe 16; such pipe at its inner end feeding a manifold 28 which communicates with and supports a plurality of vertical spray pipes 29 which depend into the cylinder 4 in symmetrically spaced relation.

The spray pipes 29 each include spray openings 30 which discharge radially of the cylinder 4 in the direction of the lining 24; such spray pipes depending to a lower end termination below the cylinder 4 and there being stabilized by brackets 31 secured within a gangue receiving bowl 32, having a top neck 33 through which the lower end portion of the cylinder 4 depends in rotatable relation.

The bowl 32, which is of substantial depth, is supported in the frame 1 by bracing 34. A discharge pipe 35 leads from the bottom of the bowl 32, and such pipe includes an upstanding neck 36 which terminates in said bowl in a horizontal plane a distance above the bottom of the latter whereby a pocket 37, for the reception of amalgam, is formed in the bottom of said bowl. A drain plug 38 is threaded into the bowl bottom at the low point thereof.

At its upper end the neck 36 is fitted with a collector, indicated generally at 39. Such collector 39 comprises a plurality of circumferentially spaced horizontally disposed V shaped vanes 40 which lie with their apices outermost. The vanes 40 diagonal contra to the direction of rotation of the cylinder 4; such vanes being secured at their inner lower ends to the neck 36, and otherwise being connected in unitary relation by rings 41 and 42.

In operation of the above described centrifugal amalgamator, the amalgamating cylinder 4 is first placed in rotation by actuation of the electric motor 15. With mercury in the receptacle 22, the valve 23!: is then opened to allow mercury to enter the topmost groove 25. When such groove is filled and the mercury overflows and drains down the outside wall of the groove, it is thrown by centrifugal force into the next groove below, and so on until all the grooves are filled. Sufficient mercury is thus introduced into the cylinder to substantially fill all of the lining grooves 25; the mercury, indicated at 43, being maintained in the grooves 25 by centrifugal force.

After the grooves 25 are filled with mercury, as above, the valve 230 is closed and fine crushed ore pulp is fed through pipes 16, distributor pipes and nozzles 21 into the cylinder 4 at its upper end.

The pulp as thus fed into the cylinder 4 is held by centrifugal force on the lining 24, yet begins a downward travel, by gravity, toward the lower end of said cylinder. At the same time, the valve 27 is opened so that water, under pressure, sprays forcefully from the openings 36 in spray pipe 29. Such spray of water not only has the effect of flushing or washing the pulp downwardly in the cylinder 4 but also acts to cause impingement of the values in the pulp with the mercury 43 in the grooves 25, greatly aiding in the amalgamation process.

By the time the pulp reaches the lower end of the cylinder 4, substantially all of the values have been amalgamated with the mercury 43 in the grooves the gangue, as. now carried in a substantial quantity of water, delivering from the lower end of cylinder 4 into the bowl 32. Because of the fact that the direction of delivery of the gangue into the bowl 32 is rotary, a constant circulation of the gangue and water is maintained therein, so that any values which remain in the gangue tend to gravitate into the pocket 37 for subsequent recovery.

The circulating gangue and water in the bowl 32 are constantly received by the collector 39 and thence flow downwardly into neck 36 and are carried by the pipe to a suitable discharge point.

In order to prevent upward splash of the pulp or water from the upper end of the cylinder 4 during operation of the machine, said cylinder is fitted at the upper end with an annular inwardly inclined anti-splash flange 44.

After the machine has been in operation a length of time, predetermined by the anticipated amalgamation of the values with the mercury 43, the feed of the pulp from pipes 16 is discontinued; the water spray from pipe 29 being continued for a sufficient length of time to complete the amalgamation process with respect to the pulp remaining in the cylinder, and to flush all of the gangue from said cylinder into the bowl 32. Thereafter the valve 27 is closed, and the bowl 32 drains to the level of the upper end of neck 36.

Nextly, thev electric motor 15 is deenergized and when the cylinder 4 comes to a stop, substantially all of the amalgamated mercury 43 gravitationally displaces from the grooves 25 and falls from the cylinder 4 into the bowl 32, being received in the pocket 37. The amalgamated mercury is then withdrawn from the pocket 37, for subsequent processing for recovery of the values, by re moval of the drain plug 38.

With the described centrifugal amalgamator, which has a relatively large capacity, values can be recovered-by the amalgamation processfrom fine crushed pulp in an efiicient and economical manner.

it should here be noted that under certain conditions at least, compressed air, or the like, may be used instead or" water in the spray pipes, and also in the feed pipe.

From the foregoing description it will be readily seen that there has been provided such a device as substantially fulfills the objects of the invention as set forth herein.

(Write this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent are desired:

1. A centrifugal amalgamator comprising a frame, an open-ended cylinder journaled on the frame and disposed in an upstanding position, means to rotate the cylinder, the latter having an internal wall adapted to retain mercury by centrifugal force upon rotation of the cylinder, means to feed mercury and ore pulp into the rotating cylinder in succession and adjacent the upper end thereof, means to separately introduce a liquid into said rotating cylinder against said internal wall below said feeding means, a receiving bowl at the lower end of the cylinder, and an outlet from the bowl above the bottom of the latter whereby to define an amalgam receiving pocket in the bowl below said outlet.

2. A centrifugal amalgamator, as in claim 1, in which the bowl is stationary, surrounds the lower end portion of the cylinder, and depends below the latter; said outlet being a pipe neck upstanding from the bottom of the bowl, and a collector on the upper end of the neck.

3. A centrifugal amalgamator, as in claim 2, in which the collector includes a plurality of circumferentially spaced vanes extending laterally outwardly above the upper end of the neck, and being angled rearwardly relative to the direction of rotation of the cylinder.

4. A centrifugal amalgamator comprising a frame, an upstanding cylinder journaled in the frame, means to rotate the cylinder, the latter having an internal wall formed with a multiplicity of indentations adapted to retain mercury by centrifugal force upon rotation of said cylinder, means to feed mercury and ore pulp in succession into the rotating cylinder adjacent its upper end, means to spray water against said internal wall, a receiv ing bowl in communication with and depending below the cylinder, and an outlet from the bowl above the bottom of the latter.

5. A centrifugal amalgamator comprising a frame, an upstanding cylinder journaled in the frame, means to rotate the cylinder, a lining in the cylinder, said lining having a multiplicity of circumferential vertically spaced grooves therein adapted to retain mercury by centrifugal force upon rotation of said cylinder, means to feed mercury and ore pulp in succession into the rotating cylinder adjacent its upper end, means to spray water against said internal wall, a receiving bowl in communication with and depending below the cylinder, and an outlet from the bowl above the bottom of the latter.

6. A centrifugal amalgamator, as in claim 5, in which said lining is formed of resilient material.

7. A centrifugal amalgamator comprising a frame, an upstanding cylinder journaled in the frame, means to rotate the cylinder, the latter having an internal wall formed with a multiplicity of indentations adapted to retain mercury by centrifugal force upon rotation of said cylinder, a feed pipe overhanging the cylinder, said pipe including a plurality of distributor legs depending into the upper portion of the cylinder in circumferentially spaced relation, a nozzle on the lower end of each distributor pipe adjacent said wall and opening in the directicn of rotation of the cylinder, means to introduce mercury and ore pulp into the feed pipe in succession, means to spray water against said internal wall, a receiving bowl in communication with and depending below the cylinder, and an outlet from the bowl above the bottom of the latter.

8. A centrifugal amalgamator comprising a frame, an upstanding cylinder journaled in the frame, means to rotate the cylinder, the latter having an internal wall formed with a multiplicity of indentations adapted to retain mercury by centrifugal force upon rotation of said cylinder, a feed pipe overhanging the cylinder, said pipe including a plurality of distributor legs depending into the upper portion of the cylinder in circumferentially spaced relation, a nozzle on the lower end of each distributor pipe adjacent said wall and opening in the direction of rotation ofthe cylinder, means to introduce-mer- 6 cury and one pulp into the feed pipe in succession, a spray pipe extending lengthwise in the cylinder operative to discharge Water against said internal wall, a receiving bowl in communication with and depending below the cylinder, and an outlet from the bowl above the bottom of the latter.

References Cited in the file of this patent UNITED STATES PATENTS 894,632 Hall et al. July 28, 1908 1,284,963 Anderson Nov. 19, 1918 1,336,968 Lapham Apr. 13, 1920 1,623,421 Lewis Apr. 5, 1927 FOREIGN PATENTS 17,487/34 Australia June 10, 1935 

